(PowerShell) IMAP Search with THREAD Semantics

Demonstrates how to search an IMAP mailbox and return message numbers grouped together in parent/child relationships based on which messages are replies to others.

Note: This example requires Chilkat v9.5.0.77 or greater.

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Add-Type -Path "C:\chilkat\ChilkatDotNet47-9.5.0-x64\ChilkatDotNet47.dll"

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

$imap = New-Object Chilkat.Imap

# Connect to your IMAP server and authenticate..
$imap.Ssl = $true
$imap.Port = 993
$success = $imap.Connect("imap.mail.us-west-2.awsapps.com")
if ($success -ne $true) {
    $($imap.LastErrorText)
    exit
}

$success = $imap.Login("myLogin","myPassword")
if ($success -ne $true) {
    $($imap.LastErrorText)
    exit
}

# Select a mailbox
$success = $imap.SelectMailbox("Inbox")
if ($success -ne $true) {
    $($imap.LastErrorText)
    exit
}

# Search for all message having the letter 'a' somewhere in the Subject,
# and return the messages as JSON.
$json = $imap.ThreadCmd("REFERENCES","UTF-8","SUBJECT a",$true)
if ($imap.LastMethodSuccess -eq $false) {
    $($imap.LastErrorText)
    exit
}

# The IMAP server will return a raw response with a format such as this:  (2)(3 6 (4 23)(44 7 96))

# In tree form, it's like this:
# 
#             -- 2
#             -- 3
#                 \-- 6
#                    |-- 4
#                    |      \-- 23
#                    |
#                    |-- 44
#                               \-- 7
#                                       \-- 96
# 

# It means there are 2 main threads returned, but the 2nd thread splits into two sub-threads.
# In total, we can think of it as 3 threads -- 2 main threads (with no parents) and one sub-thread w/ a parent.
# 
# - The 1st thread contains the message 2, and has no parent thread.
# - The 2nd thread contains the messages 3, 6, 4, 23, and has no parent thread.
# - The 3rd thread contains the messages 44, 7, 96 and the parent thread is message 6.
# 

# (Yes, this is all highly confusing...)

# Chilkat will return the above sample response as JSON that looks like this:

# {
#   "threads": [
#     [2],
#     [3, 6, [4, 23], [44, 7, 96]]
#   ]
# }
# 

# Use this online tool to generate parsing code from sample JSON: 
# Generate Parsing Code from JSON
# In this case, the online tool can help you get a feel for how to write the JSON parsing code..

$numThreads = $json.SizeOfArray("threads")
$("The total number of top-level threads is " + $numThreads)

# Let's say we wanted to get the messages in the thread 3, 6, 4, 23.
# We always follow the 1st branch to the bottom, ignoring the other branches.
# For example, if we had  [3, 5, [4, 23, [55, 56, 57], [68, 69]], [44, 7, 96]]
# then the thread would be 3, 5, 4, 43, 55, 56, 57

# For testing, let's substitute the response from the IMAP server with this sample:
$json.Load("{`"threads`": [[2], [3, 5, [4, 23, [55, 56, 57], [68, 69]], [44, 7, 96]]]}")

# Begin with the 2nd top-level thread, which is at index 1.
$("Following the 2nd top level thread...")
$arr = $json.ArrayOf("threads[1]")
$threadSize = $arr.Size
$i = 0
while ($i -lt $threadSize) {
    # Do we have an array or integer at this position?
    if ($arr.TypeAt($i) -eq 4) {
        # This is a sub-array.
        $subArr = $arr.ArrayAt($i)

        # Follow the sub-array starting at the 1st position..
        $arr = $subArr
        $i = 0
        $threadSize = $arr.Size
    }
    else {
        # Must be a single integer.
        $($arr.IntAt($i))
        $i = $i + 1
    }

}

# The output is:
# 
# Following the 2nd top level thread...
# 3
# 5
# 4
# 23
# 55
# 56
# 57